The present invention relates generally to file system extended attributes, and more specifically, to supporting file system extended attributes in an operating system with restricted extended attributes.
File systems are used to organize data expected to be retained after a program terminates by providing procedures to store, retrieve, and update data as well as procedures to manage the available space on the storage devices that contain the data. Typically file systems organize data in an efficient manner that is tuned to the specific characteristics of the storage devices. In addition, file systems provide mechanisms to control access to the data and metadata. Metadata is a type of bookkeeping information that is associated with a file such as the time that the file was last modified, the file creation time, the time the file was last accessed, the time the file metadata was changed, the time the file was last backed up, the file owner, and/or the access permission settings (e.g., whether the file is read-only, executable, etc.). Generally, metadata is used by the file system and has a purpose that is strictly defined by the file system.
File system extended attributes associated with a file include user defined attributes such as an author of the file, a character encoding of the file, a checksum of the file, and/or the size of an image in the file. File system extended attributes typically contain data used by the applications that access the file.